Chemical sensitization of photothermographic silver halide emulsions
Chemical sensitization of silver halide photothermographic emulsions used in photothermographic elements, can be effected by the decomposition of sulfur containing compounds on or around the surface of the silver halide grains, usually under oxidizing conditions at elevated temperatures. Alignment of the sulfur containing compounds on the surface of the grains, can be accomplished with spectral sensitizing dyes and appears to be particularly effective in providing strong chemical sensitization effects.
Latest Imation Corp. Patents:
- Methods for control of digital shredding of media
- Archiving system with partitions of individual archives
- Logical-to-physical address translation for a removable data storage device
- Portable desktop device and method of host computer system hardware recognition and configuration
- Sound pressure level limiting
Claims
1. A method for preparing a photothermographic emulsion comprising the steps of:
- (a) providing a photothermographic emulsion comprising silver halide grains and a non-photosensitive silver source;
- (b) providing an organic sulfur-containing compound positioned on or around the silver halide grains; and
- (c) chemically sensitizing the silver halide grains by decomposing the organic sulfur-containing compound on or around the silver halide grains in an oxidizing environment.
2. The method of claim 1 which the chemical sensitizing step comprises reacting the sulfur compound from the decomposed organic sulfur-containing compound with the silver halide grains.
3. The method of claim 1 in which the decomposing produces HSBr which chemically sensitizes the silver halide grains.
4. The method of claim 1 in which after chemical sensitization of said silver halide grains, a spectral sensitizing dye is added to said photothermographic emulsion to spectrally sensitize said emulsion.
5. The method of claim 1 wherein said silver halide grains are iridium-doped silver halide grains.
6. The method of claim 1 wherein said silver halide grains comprise silver halide grains which are iridium doped core-shell silver halide grains and after chemical sensitization of said silver halide grains, a spectral sensitizing dye is added to said photothermographic emulsion to spectrally sensitize said emulsion.
7. The method of claim 6 wherein said spectral sensitizing dye sensitizes the chemically sensitized silver halide grains of the photothermographic emulsion to the red or infrared region of the electromagnetic spectrum between 600 nm and 1000 nm.
8. The method of claim 1 further comprising adding a reducing agent to the sensitized photothermographic emulsion.
9. The method of claim 1 wherein the sulfur-containing compound comprises a ring structure having --S-- or ##STR21## within the ring.
10. A method for preparing a photothermographic emulsion comprising the steps of:
- (a) providing a photothermographic emulsion comprising silver halide grains and a non-photosensitive silver source;
- (b) providing a sulfur-containing spectral sensitizing dye positioned on or around the silver halide grains; and
- (c) chemically sensitizing the silver halide grains by decomposing the spectral sensitizing dye on or around the silver halide grains.
11. The method of claim 10 in which after chemical sensitization of said silver halide grains, a second spectral sensitizing dye is added to said photothermographic emulsion to spectrally sensitize said emulsion.
12. A method for preparing a photothermographic emulsion comprising the steps of:
- (a) providing a photothermographic emulsion comprising silver halide grains and a non-photosensitive silver source;
- (b) providing a sulfur-containing compound comprising a thiohydantoin nucleus, a rhodanine nucleus, or a 2-thio-4-oxo-oxazolidine nucleus positioned on or around the silver halide grains; and
- (c) chemically sensitizing the silver halide grains by decomposing the sulfur-containing compound on or around the silver halide grains.
13. A method for preparing a photothermographic emulsion comprising the steps of:
- (a) providing a photothermographic emulsion comprising silver halide grains and a non-photosensitive silver source;
- (b) providing a sulfur-containing compound positioned on or around the silver halide grains; and
- (c) chemically sensitizing the silver halide grains by providing an oxidizing compound which causes the decomposing of the sulfur-containing compound on or around the silver halide grains.
14. The method of claim 13 wherein the oxidizing compound is present in a solution, said solution is in contact with said silver halide grains, and the chemical sensitizing step occurs at a temperature above about 20.degree. C.
15. The method of claim 14 where the temperature is between about 20.degree. C. and about 40.degree. C.
16. The method of claim 13 wherein said oxidizing compound is pyridinium hydrobromide perbromide.
17. A method of forming a sensitized photothermographic emulsion comprising the steps of:
- (a) providing a photothermographic emulsion comprising silver halide grains and a non-photosensitive silver source;
- (b) providing a sulfur-containing spectral sensitizing dye on or around the silver halide grains;
- (c) decomposing the spectral sensitizing dye in an oxidizing environment at a temperature between about 20.degree. C. and about 40.degree. C.;
- (d) adding a second spectral sensitizing dye to said photothermographic emulsion to spectrally sensitize said emulsion.
18. A method of making a photothermographic element comprising:
- (a) preparing a photothermographic emulsion according to claim 1;
- (b) adding a reducing agent and a binder to the photothermographic emulsion;
- (c) coating the photothermographic emulsion on a substrate.
19. A method for chemically sensitizing silver halide grains comprising the steps of:
- (a) providing a silver halide grains;
- (b) providing a sulfur-containing sensitizing dye on or around the surface of silver halide grains; and
- (c) oxidatively decomposing the sulfur-containing sensitizing dye thereby chemically sensitizing said grains.
1623499 | April 1927 | Sheppard et al. |
2131038 | September 1938 | Brooker et al. |
2399083 | April 1946 | Waller et al. |
2444605 | December 1948 | Heimbach et al. |
2489341 | November 1949 | Waller et al. |
2565418 | August 1951 | Yackel |
2566263 | August 1951 | Trivelli et al. |
2588765 | March 1952 | Robijns et al. |
2597915 | May 1952 | Yutzy et al. |
2614928 | October 1952 | Yutzy et al. |
2618556 | November 1952 | Hewitson et al. |
2681294 | June 1954 | Beguin |
2694716 | November 1954 | Allen et al. |
2701245 | February 1955 | Lynn |
2728663 | December 1955 | Allen et al. |
2761791 | September 1956 | Russell |
2839405 | June 1958 | Jones |
2861056 | November 1958 | Minsk |
2886437 | May 1959 | Piper |
2960404 | November 1960 | Milton et al. |
2992101 | July 1961 | Jelley et al. |
3080254 | March 1963 | Grant, Jr. |
3121060 | February 1964 | Duane |
3201678 | August 1965 | Meixell |
3206312 | September 1965 | Sterman et al. |
3220839 | November 1965 | Herz et al. |
3235652 | February 1966 | Lindsey |
3241969 | March 1966 | Hart et al. |
3287135 | November 1966 | Anderson et al. |
3297446 | January 1967 | Dunn |
3297447 | January 1967 | McVeigh |
3330663 | July 1967 | Weyde et al. |
3428451 | February 1969 | Trevoy |
3457075 | July 1969 | Morgan et al. |
3700458 | October 1972 | Lindholm |
3719495 | March 1973 | Lea |
3761279 | September 1973 | Mauriac et al. |
3785830 | January 1974 | Sullivan et al. |
3839049 | October 1974 | Simons |
3846136 | November 1974 | Sullivan |
3847612 | November 1974 | Winslow |
3985565 | October 12, 1976 | Gabrielsen et al. |
3994732 | November 1976 | Winslow |
4001025 | January 4, 1977 | Cash |
4021249 | May 3, 1977 | Noguchi et al. |
4076539 | February 28, 1978 | Ikenoue et al. |
4123274 | October 31, 1978 | Knight et al. |
4123282 | October 31, 1978 | Winslow |
4207108 | June 10, 1980 | Hiller |
4213784 | July 22, 1980 | Ikenoue et al. |
4220709 | September 2, 1980 | deMauriac |
4260677 | April 7, 1981 | Winslow et al. |
4374921 | February 22, 1983 | Frenchik |
4708928 | November 24, 1987 | Geisler |
4725534 | February 16, 1988 | Kagami et al. |
4761361 | August 2, 1988 | Ozaki et al. |
4775613 | October 4, 1988 | Hirai et al. |
5028523 | July 2, 1991 | Skoug |
5135842 | August 4, 1992 | Kitchin et al. |
5158866 | October 27, 1992 | Simpson et al. |
5175081 | December 29, 1992 | Krepski et al. |
5185231 | February 9, 1993 | Weigel |
5226452 | July 13, 1993 | Muller et al. |
5262295 | November 16, 1993 | Tanaka et al. |
5279928 | January 18, 1994 | Dedio et al. |
5281515 | January 25, 1994 | Delprato et al. |
5298390 | March 29, 1994 | Sakizadeh et al. |
5300420 | April 5, 1994 | Kenney et al. |
5310640 | May 10, 1994 | Markin et al. |
5314795 | May 24, 1994 | Helland et al. |
5340613 | August 23, 1994 | Hanzalik et al. |
5380635 | January 10, 1995 | Gomez et al. |
5380644 | January 10, 1995 | Yonkoski et al. |
5382504 | January 17, 1995 | Shor et al. |
5434043 | July 18, 1995 | Zou et al. |
5441866 | August 15, 1995 | Miller et al. |
5460938 | October 24, 1995 | Kirk et al. |
5491059 | February 13, 1996 | Whitcomb |
5496695 | March 5, 1996 | Simpson et al. |
5541054 | July 30, 1996 | Miller et al. |
5541055 | July 30, 1996 | Ooi et al. |
5545505 | August 13, 1996 | Simpson |
5545507 | August 13, 1996 | Simpson et al. |
5545515 | August 13, 1996 | Murray et al. |
5558983 | September 24, 1996 | Simpson et al. |
5635339 | June 3, 1997 | Murray |
5637449 | June 10, 1997 | Harring et al. |
5654130 | August 5, 1997 | Murray |
5686228 | November 11, 1997 | Murray et al. |
5705324 | January 6, 1998 | Murray |
0600589 | June 1994 | EPX |
0 627 660 | December 1994 | EPX |
0 713 132 | May 1996 | EPX |
49-13224 | February 1974 | JPX |
51-42529 | April 1976 | JPX |
52-126780 | October 1977 | JPX |
623448 | May 1949 | GBX |
837095 | June 1960 | GBX |
955061 | April 1964 | GBX |
1 325 312 | August 1973 | GBX |
1 447 454 | August 1976 | GBX |
WO 95/23357 | August 1995 | WOX |
Type: Grant
Filed: Apr 8, 1997
Date of Patent: Apr 6, 1999
Assignee: Imation Corp. (Oakdale, MN)
Inventors: John M. Winslow (South St. Paul, MN), Gary L. Featherstone (Oakdale, MN), Doreen C. Lynch (Afton, MN), James R. Miller (Hudson, WI), Sharon M. Simpson (Lake Elmo, MN), Mark C. Skinner (Afton, MN)
Primary Examiner: Thorl Chea
Attorney: William K. Weimer
Application Number: 8/841,953
International Classification: G03C 109; G03C 100;